Subjects

Abstract

We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 3 April – 11 September 2015. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2015 were to: 1) estimate the size of the adult Snowy Plover population along the Oregon coast, 2) locate plover nests, 3) determine nest success, 4) implement nest protection as appropriate (e.g. ropes, signs, exclosures), 5) determine fledging success, 6) monitor brood movements, and 7) collect general observational data about predators.

We estimate the Snowy Plover breeding population in Oregon at 449 individuals; a minimum of 376 individuals were known to have nested. The adult plover population was the highest estimate recorded since monitoring began in 1990. We monitored 501 nests in 2015. Overall apparent nest success was 48%. Nest failures were attributed to unknown cause, unknown depredation, mammalian depredation, corvid depredation, abandonment, wind/weather, one-egg nests, harrier depredation, infertility, overwashing, gull depredation and human caused. We monitored 271 broods, including 32 from unknown nests, and documented a minimum of 333 fledglings. Overall brood success was 75%, fledging success was 49%, and 1.51 fledglings per male were produced.